1. Field of the Invention
The present invention relates to snow and ice melting equipment. More particularly, the present invention relates to equipment for maintaining sidewalks, driveways, and roofs free of ice and snow.
2. Description of the Related Art
The use of heating coils or the like to maintain surfaces such as sidewalks, driveways, and roofs free from buildup of ice and snow is known. Commonly used devices include steam or hot water heated coils within or underneath the surface material such as concrete or the like. Also known is the use of electrical resistance heating systems including mats for placement over the surface to be cleared having resistance heating elements therein. In some applications resistance electrical heating mats are uneconomical. It would be desirable to provide an alternative mat type system which may use recirculated heated air and which may be placed on the surface to be kept clear of snow, such as a driveway, and is sufficiently sturdy to walk or drive a car over without damage.
U.S. Pat. No. 223,784, issued Jan. 20, 1880, to Watson, describes a sidewalk having a fluid circuit of tubes under the surface for conveying steam for heating the sidewalk to prevent snow and ice from accumulating on the surface.
U.S. Pat. No. 3,818,892, issued Jun. 25, 1974, to Von Kohorn, describes a system for removing snow and ice from an athletic playing surface where heated air is circulated beneath the surface and up through the porous playing surface.
U.S. Pat. No. 4,270,596, issued Jun. 2, 1981, to Zinn et al., describes a heat exchanger for use in embedded radiant heating systems including a plurality of webbed tube mats and associated manifolds.
U.S. Pat. No. 4,646,818, issued Mar. 3, 1987, to Ervin, Jr., describes heated mats for melting snow and ice from walkways, driveways, and sidewalks employing tubing carrying a heated mixture of water and antifreeze.
U.S. Pat. No. 5,003,157, issued Mar. 26, 1991, to Hargrove, describes a snow melting pathway mat apparatus which is electrically heated and includes hollowed channels extending longitudinally along the mat, allowing melted snow to flow off the mat.
U.S. Pat. No. 5,591,365, issued Jan. 7, 1997, to Shields, describes a lattice-like heating mat having electrical resistance heating wire extending through the lattice, the lattice configuration allowing flexibility in conforming to uneven surfaces and for rolling up for storage.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed. Thus a mat system using recirculated heated air to melt snow solving the aforementioned problems is desired.